The present invention relates to a control circuit for controlling a power semiconductor, the control circuit comprising a gate driver comprising a control input, auxiliary voltage inputs and an output.
For some time, gate drivers equipped with optical isolation have been commercially available that can be used for controlling at most an approximately 100-ampere power semiconductor, such as an IGBT or FET. The reason for the limited power semiconductor rating is the limited current output capacity of a gate driver, which makes it impossible to control high-current power semiconductors in a reliable manner. Because of the above-mentioned problem, using such a gate driver necessitates a separate amplifier stage by means of which the current feeding capacity can be made to satisfy the needs of larger power semiconductors as well.